const skyDom = document.getElementsByClassName('sky')[0];
const skyStyle = getComputedStyle(skyDom);
const skyWidth = parseFloat(skyStyle.width); //天空宽度
const skyHeight = parseFloat(skyStyle.height); //天空高度
const skyLeft = parseFloat(skyStyle.left); //位置
const skyTop = parseFloat(skyStyle.top);
class Sky extends JuXing {
    constructor() {
        super(skyWidth, skyHeight, skyLeft, skyTop, -50, 0, skyDom);
    }
    onMove() {
        if (this.left <= -skyWidth / 2) {
            this.left = 0;
        }
    }
}